A faithless super PAC

12/29/11 2:11 PM EST

A political action committee which had planned to support Michele Bachmann's presidential campaign has very quietly defected to Mitt Romney — and it's spending big on his behalf.

Citizens for a Working America, the so-called Super PAC which aired TV ads against a Democratic congressional candidate last year, had indicated earlier this year that it was backing the Minnesota congresswoman in the GOP nominating contest. But the group instead made a $475,000 Iowa ad buy on Christmas Eve in support of Romney, according to Federal Election Commission data published today.

The so-called independent expenditure was listed as supporting Romney's candidacy, and an Iowa political operative who has seen the ad confirmed to The Daily that it's a 30-second positive spot about the former Massachusetts governor that doesn't mention any other candidate.